most buylists pay $3-$4 per thousand and shipping in a Medium Flat Rate will cost you $2-$2.50 per thousand, you so basically end up making $8 for thousands of cards
Some of them may show up elsewhere
This iteration is Marchesa, the Black Rose, and costs four mana for a 3/3 with dethrone, and they give you other Creatures dethrone too
Number 23 Language English Legal Formats Commander, Legacy, Pauper, Vintage Not Legal Formats Alchemy, Brawl, Competitive Brawl, Historic, Pioneer, Standard, Timeless Rulings (12/8/2022) You choose the target for Dread Return before paying any of its costs, so it's not possible to cast it using flashback and bring back one of the creatures you sacrifice
There was a cycle of these creatures with Bestow with a drawback, the idea being that you can use them either on your own creature or an opponents creature